import java.util.ArrayList;

public class Test1 {
    public static void main(String[] args) {
        int[]arr={1};
        int len=arr.length;
        ArrayList arrayList=new ArrayList<>();
        arrayList.size();
//        MyArrayList<String> myArrayList=new MyArrayList<>();
//        myArrayList.add("123");
//        System.out.println(myArrayList);
//
//        var a="dimfkidf";
//        ArrayList<String> list=new ArrayList<>();
//        Demo1.addAll(list,"20","30");
//        System.out.println(list);
    }
}
